Prostate cancer is the most common noncutaneous cancer in males and the second most common cause of cancer-related death in men in the United States (Jemal et al. (2008) CA Cancer J. Clin. 58:71-96; herein incorporated by reference in its entirety). The American Cancer Society estimates that in 2009, 92, 280 new cases of prostate cancer will be diagnosed and 27,360 men will die of prostate cancer. The incidence of prostate cancer diagnosis in men exceeds 1 in 6, and the death rate due to prostate cancer is approximately 1 in 35. Standard treatment of advanced and/or metastatic prostate cancer includes androgen suppression, cytotoxic chemotherapy, and radiation. These treatment modalities carry significant side effects, and treatment regimes (and consequently likelihood of success) are far more limited for hormone-refractory prostate tumors than hormone-responsive tumors. For metastatic prostate cancer, no form of therapy is curative, and thus this represents a terminal diagnosis. Surgical approaches and radiation, typically in combination with hormone therapy, may be used for intermediate-stage tumors; however, again, these modalities carry significant risk of undesirable side effects such as incontinence and/or impotence. For early-stage tumors, standard approaches consist of surgery, radiation (which may be combined with hormone therapy) or watchful waiting. With watchful waiting, consensus guidelines related to its implementation are lacking, changes in clinical parameters with time lead to frequent repetitive biopsies, and with the knowledge that they have confirmed prostate cancer patients experience high levels of anxiety. All of these factors contribute to a channeling of patients into eventual treatment with surgery or radiation. Prostate cancer can be prevented by finasteride. Finasteride blocks 5-alpha reductase and inhibits the synthesis of dihydrotestosterone. Treatment with finasteride daily for five years reduces prostate cancer incidence by 25%. However, impotence is a major side effect, is not acceptable to most people, and thus finasteride use is limited.
Better treatment of prostate cancer is needed. In particular, agents that prevent prostate cancer metastasis are needed.